package com.itheima.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import java.io.IOException;
//@WebFilter(urlPatterns = "/*")
public class DemoFilter implements Filter {

    @Override//初始化的方法，只被调用一次
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("init 初始化方法执行了");
    }

    @Override//拦截到请求之后调用，调用多次
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        System.out.println("demo拦截到了请求,放行前的逻辑");
        //放行
        //传入请求对象和响应对象
        chain.doFilter(request,response);

        System.out.println("demo放行后的逻辑");
    }

    @Override//销毁方法，只调用一次
    public void destroy() {
        System.out.println("destroy销毁方法执行了");
    }
}
